Relationship between rosacea and dietary factors: A multicenter retrospective case-control survey.

Although patients with rosacea often consult dermatologists for dietary factors that might be related to their skin disorders, few studies have been conducted to research the relationship between rosacea and dietary factors. The purpose of this study was to evaluate the potential relationship between rosacea and diet among the large Chinese population with rosacea, which would provide dietary guidelines for patients with rosacea. A multicenter case-control study was conducted. The feeding frequency 2 years before the occurrence of rosacea was collected by standardized questionnaires. Multiple logistic regression analysis was used to calculate risks related to the diet. One thousand three hundred and forty-seven patients with rosacea and 1290 controls were enrolled in our study. We found that high-frequency intake of fatty food and tea presented a positive correlation with rosacea, while high-frequency dairy product intake showed significant negative correlation with rosacea. Sweet food, coffee and spicy food appeared to be independent of any subset of rosacea in our study. However, high-frequency dairy product intake showed a borderline beneficial effect on rosacea severity. We further analyzed the correlation between diet and the subtype of rosacea. We found that high-frequency fatty intake was associated with erythematotelangiectatic rosacea (ETR) and phymatous rosacea, while high-frequency tea intake was only associated with ETR. In addition, high-frequency dairy product intake showed negative correlations with ETR and papulopustular rosacea. Rosacea is associated with some dietary factors, and our study is valuable in establishing dietary guidelines to prevent and improve rosacea.

Induction of melasma by 1064-nm Q-switched neodymium:yttrium-aluminum-garnet laser therapy for acquired bilateral nevus of Ota-like macules (Hori nevus): A study on related factors in the Chinese population.

Laser treatment has emerged as a common treatment modality for acquired bilateral nevus of Ota-like macules (ABNOM). To identify the ratio of melasma induction and exacerbation before and after laser therapy for ABNOM and to observe the risk factors related to the induction and exacerbation of melasma by laser therapy, we analyzed related factors of 1268 adult Chinese patients who underwent 1064-nm Q-switched neodymium:yttrium-aluminum-garnet (Nd:YAG) laser (QNYL) treatment using case series and case-control studies. Overall, 24.0% of the ABNOM patients had mixed melasma. Among the ABNOM patients without melasma, after laser therapy the development of melasma was more frequently noted in patients older than 35 years (P < 0.0001), as well in patients whose ABNOM was less than 10 cm(2) (P = 0.027), ABNOM were light (similar to yellow-brown) in color (P = 0.021) and skin types were closer to type IV (P < 0.0001). New melasma lesions also appeared most frequently in the zygomatic region (P < 0.0001). Among the ABNOM patients with melasma, 89.5% experienced worsening of their melasma, irrespective of their related factors above. We concluded that the risk of inducing melasma is great after 1064-nm QNYL treatment in ABNOM patients, and particularly in the patients with both ABNOM and melasma. ABNOM patients should be treated as early as possible and before the age of 35 years.